Spanish investigators randomized 7,447 people at high risk for cardiovascular disease to one of three groups: a Mediterranean diet supplemented with extra-virgin olive oil, a Mediterranean diet supplemented with nuts, or a control group in which people were advised to lower their intake of dietary fat. The diets were designed not to restrict calories but to change the composition of the diet.

The trial was stopped early in July 2011 by the data and safety monitoring board when the benefits in the Mediterranean diet groups crossed a predetermined boundary….

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One PREDIMED investigator, Emilio Ros, told CardioBrief that he believes the results of the trial mean that current recommendations regarding dietary fat should be changed to reflect that a “high fat, high vegetable fat diet is optimal for cardiovascular health.” Another study investigator, Ramón Estruch, said that “a major problem with lowfat diets is their low potential for long-term sustainability.” He said that “the results clearly demonstrate “the superiority of the Mediterranean diets.”